feat: add UniqueByParallel for slice

slice/slice_test.go

@@ -1448,3 +1448,17 @@ func TestRightPaddingAndLeftPadding(t *testing.T) {
 	padded := LeftPadding(RightPadding(nums, 0, 3), 0, 3)
 	assert.Equal([]int{0, 0, 0, 1, 2, 3, 4, 5, 0, 0, 0}, padded)
 }
+
+func TestUniqueByParallel(t *testing.T) {
+	t.Parallel()
+
+	assert := internal.NewAssert(t, "TestUniqueByParallel")
+
+	nums := []int{1, 2, 3, 1, 2, 4, 5, 6, 4, 7}
+	numOfThreads := 4
+	comparator := func(item int, other int) bool { return item == other }
+
+	result := UniqueByParallel(nums, numOfThreads, comparator)
+
+	assert.Equal([]int{1, 2, 3, 4, 5, 6, 7}, result)
+}